Metallurgical furnace of the suspended arch type



Feb. 4, 1936.

K. A. LINDYNERV METALLURGICAL FURliAGE OF THE SUSPENDED ARCH TYPE Filed May 51, 1933 IIYVENTOR. {Tar/19. [trainer B ATTORNEYS.

ures common in the sprung arch construction Patented F el). 4, 1 936 2,029,492 PATENT OFFICE METAILURGICAL FURNACE or 'r'np SUSPENDED ARCH TYPE Karl A. Lindner, Roselle Park, N.. J., assignor to American .Smelting and Refining Company, New York, N. Y., a corporation of New Jersey Application May 31, 1933, Serial No. 673,674

12 Claims. (01. 263-46) This invention relates to metallurgical furnaces of the suspended arch type and particularly concerns improvements in the side wall construction of such furnaces.

Prior to the, introduction of furnaces of the suspended arch type, which type shall be understood in the present specification and claims to designate furnaces in which the roof or arch is supported independently of the side wall, it was usual in the metallurgical art to employ furnaces of the so-called spring arch type in which the arch or roof sprung from the side 4 walls and was supported thereby. Certain defects were, however, inherent in the construction of furnaces of the sprung arch type. For example, the choice of materials for building the side walls was limited to relatively strong materials as the side walls supported the entire weight of the roof. In order to decrease damage to the side walls, attempts were often made to employ lighter materials in the construction of the roof arch, but, while such construction decreased failures in the side walls, failures in the arches increased. Theseand other disadvantages attending the sprung arch construction led to the development of furnaces of the suspended arch type.

With the advent of furnaces in which the roof was independently supported of the side walls, many of the disadvantages accompanying the old sprung arch construction were eliminated. By independently suspending the roof and thus removing the load from the side walls, the range of materials used in both. side wall and roof construction was widened and many of the failwere eliminated.

However, furnaces of the suspended arch type when employed for the treatment of metals of a high specific gravity, as, for example, lead or alloys thereof, have not been entirely satisfactory due to recurring failures of the side walls.

In fact, side wall failures in the case of furnaces operating on such materials occur so frequently that the use of suspended arch furnaces has often been abandoned in spite of the many other desirable features attending such construction. I have found that the repeated side wall failures in metallurgical furnaces of the suspended arch type are due to vertical movement of the side walls themselves. In other words, the side walls By my invention it is possible to, greatly reduce or practically eliminate failures of the side walls in metallurgical furnaces employing the suspended arch type of construction. To accomplish this desired objective I anchor the side walls at a point above the metal or bath line of the furnace in such manner that vertical movement of the refractory material comprising the side walls is prevented.

Although the novel features which are believed to be characteristic of this invention will be particularly pointed out in the claims appended hereto, the invention itself, as to its objects and advantages, and the manner in which it may be carried out, may be better understood by re-. ferring to the following description takenin connection with the accompanying drawing forming a part thereof, in which Fig. 1 is a cross-sectional view of a reverberatory furnace of the suspended arch type embodying the principles of the present invention;

Like reference characters denote like parts in the several figures of the drawing.

In the following description and in the claims,

various details will be identified by specific names;

for convenience, but they are intended to be as' mit.

Referring now to the drawing, a reverberatory furnace is shown with buckstays 9, refractory side walls [0 and roof I l suspended by hangers l2. Brackets l3 affixed to side plates 14 pro ect generic in their application as the art will per- 3O into and are embedded in refractory wall Ill.

Walls Ila provide a water 'jacket extending to substantially the height of the metal or bath line l5, while I6 indicates the space in the jacket for the circulation of water.

In operation, the brackets l3 aflixed as by welding to the side plates M which in turn are secured to buckstays S in the same or a similar manner serve to anchor the refractory material comprising the side walls and resist upward vertical movement of the side walls when the furnace is in use. By thus inhibiting the upward vertical movement of the refractory walls the molten metal in the furnace is unable to penetrate the walls with the result that side wall failures, not uncommonly experienced in suspended arch furnaces, are largely eliminated.

While in the specific embodiment of the inven tion shown in the accompanying drawing vertical movement of the side walls is prevented by means of brackets welded to the side plates and embedded in the-refractory w'alls above the metal line of the bath, other means of inhibiting the vertical movement referred to may be employed.

For example, brazed beams extending along the top of the refractory side walls and suitably anchored may be used. Again other types of anchoring means suitably affixed to the side plates which will inhibit vertical side wall movement will be apparent to those skilled in the art.

It will thus be appreciated that the present invention by greatly reducing the number of side wall failures and eliminating the cause thereof makes possible the commercial use of metallurgical furnaces having independently supported roofs in treating metals w high'speciflc gravities, as, for example, lead an alloys thereof.

While certain novel features of the invention have been disclosed and are pointed out in the annexed claims, it will be understood that various omissions, substitutions and changes may be made by those skilled in the art without departing from the spirit of the invention.

and embedded in said walls whereby vertical movement 'of said refractory .walls is prevented.

3. In a metallurgical furnace of the suspended arch type for treating metals of high specific gravity, vertical side walls formed of blocks of refractory material, said side walls being in direct contact with the molten metal below the metal line in said furnace and extending above said metal line, metal side plates covering the outside of said side walls and secured to an outer retaining framework, and brackets'secured t0 the inside surfaces of said side plates and embedded in said side walls to prevent vertical movement of said walls.

4.'In a metallurgical furnace of the suspended arch type, vertical side walls and a separately suspended roof of refractory material, said side walls extending from below the metal line. of said furnace to said roof, an outer retaining member and brackets secured thereto and embedded in said side walls intermediate said roof and said metal line to retain the lower portions of said walls in place.

5. In ametallurgicalfurnaceofthe arch type for treating metals of h gh density, vertical side walls of refractory material, a roof, said side walls extending from below the metal lineinsaidfurnacetosaidrooLametalframe work outside said furnace supporting said roof,

and brackets secured to said framework and em-- forcing frame' adjacent to. the side walls, and brackets embedded in the'side walls and rigidly v secured to the said reinforcing for overcomingtendencyof'thesidewallstomoveunder reinforcing the brackets, the said brackets and webs being adapted to overcome movement of the side walls under the action of molten 'metal entering into openings in the side walls formed during operation of the furnace.

8. A metallurgical furnace comprising the combination with a framework and a roof suspended from the framework, of side walls cooperating with the roof but independent thereof, a reinforcing frame for the side walls including buckstays adjacent to the side walls and substantially triangular brackets embedded in the side walls and welded to the buckstays, the saidbrackets having one side extending at substantially right angles to the buckstaysand having their longest side positioned to rigidly brace the outstanding side for counteracting tendency of the side walls to become displaced under action of molten metal 7 entering openings in the said walls formed during operation of the'furnace.

9. A metallurgical furnace comprising the combination with ad'ramework and a roof suspended from the framework, of side walls cooperating with the roof but independent thereof, a reinforcing framework adjacent to the side walls and means rigidly secured to the framework and embedded in the side walls in position to counteract tendency of the side walls to become displaced under action of molten metal entering openings in the said walls.

10. A metallurgical furnace comprising the combination with a framework and a roof suspended from the framework, of side walls cooperating with the roof but independent thereof, a reinforcing framework adjacent to the side walls, and means secured to the framework and associated with the side walls in position to counteract tendency of the side walls to become displaced under buoyant action of molten metal entering openinsqin the side walls.

- 11. A metallurgical furnace comprising the combination with a framework, of a roof suspended from the framework, an outer retaining framework, side plates secured thereto, brackets integral therewith, and refractory side walls, the said brackets being anchored in the said refractory side walls at a point above the metal line of the-furnace and acting upon the sidewalls to counteract any tendency of the side walls to become displaced-through buoyant action of molten metal entering openings in the side walls.

12. A metallurgical furnace comprising, in

' combination, a suspended roof, refractory walls and anchored side plates with brackets secured thereto, the said brackets being embedded in the said refractory walls and bearingthereon to resist tendency of deformation of the walls under buoyancy of. molten metal entering openings in the said walls. v

' KARL A. LINDNER. 

